This is why the Indianapolis ice caught everyone by surprise

This road might look clear from ice... but it's not. The road in Parks Hill, Kentucky is covered with black ice. A driver slid in ice and then hit a police cruiser.
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Two cars sit on the sidelines of 56th street, Indianapolis, where crashes, delays, and slide-offs are common during a slow commute that is compounded by a layer of slick ice that fell overnight, Indianapolis, Wednesday, Jan. 24, 2018.(Photo: Robert Scheer/IndyStar)Buy Photo

"Originally, it was expected not to be quite the widespread event that we saw. Mostly it was just going to be some isolated drizzle (further to the north) but the reason it was more widespread was just that there was an upper level system," White said. "That gave it some additional forcing that was able to take the moisture in the atmosphere and create those clouds that produced that widespread freezing drizzle.

"Even though we were below freezing at the surface, at the cloud level, it was still not quite cold enough for ice formation ... when that liquid hit the surfaces this morning, that's what caused the freezing."

That change in the conditions was reflected in the forecasts and advisories issued by the National Weather Service Tuesday night. Shortly before 7 p.m. Tuesday, the service tweeted out a forecast just calling for clouds and a chance of snow flurries.

An updated forecast tweeted shortly after 11 p.m. Tuesday warned of patchy freezing drizzle and slick roads. That was followed with a map showing the formation of freezing drizzle across Central Indiana that was expected to last through 1 a.m.

It is unclear exactly what forecast the Indianapolis DPW was following and what service provided it to them, but during a Wednesday morning press conference, officials referred to a printed forecast that was issued 7 a.m. Tuesday.

The good news, White said Wednesday morning, was that the freezing drizzle has transitioned to mostly snow flurries with a little bit of sleet mixed in.

"The freezing rain should be about done for today, and we're not really expecting anything for tonight when it comes to that," White said. "Any roads that are still wet from this afternoon could freeze again tonight, but anything that has been treated should be fine."

He added that with the northern part of the state being the original target for this freezing drizzle, conditions are still very slick you head north on I-65.

"From just northwest of Lafayette into portions of Crown Point, it is still running really slow," White said. "The Chicago-area was also hit really hard."